We isolated mutant strains of the facultative anaerobe Salmonella typhimurium that grow either aerobically or anaerobically. Strict anaerobic mutants contained a defective DNA topoisomerase I gene (topI), while strict aerobic mutants contained a defective DNA gyrase subunit A gene (gyrA, also nalA). Topoisomerase I activity was detected in cell-free extracts of strict aerobic mutants but not of...

Male intrasexual competition should favour increased male physical prowess. This should in turn result in greater aerobic capacity in males than in females (i.e. sexual dimorphism) and a correlation between sexual dimorphism in aerobic capacity and the strength of sexual selection among species. However, physiological scaling laws predict that aerobic capacity should be lower per unit body mass...

background: chronic myeloid leukemia is a common cancer in human and chemical therapy is a routine method for treatment that has some side effects. so the goal of this study was the use of natural compound such as cell wall obtained from saccharomyces cerevisiae ( s. cerevisiae ) and saccharomyces boulardi ( s. boulardi ) and iron nanoparticles on the growth inhibition of k562 cell line. method...

The most immediate effect of anaerobic soil conditions on plants is a reduction in aerobic respiration in roots. Root cells switch to anaerobic respiration which is much less efficient than aerobic respiration. Under normal aerobic conditions 30 to 32 mol ATP are produced per hexose sugar by oxidative phosphorylation, citric acid cycle and glucolysis, whereas at anoxic conditions only 2 mol ATP...

To investigate the mechanisms by which heat affects cancer cells, we used 5-thio-D-glucose, an inhibitor of glycolysis in HeLa S-3 cells, under aerobic and hypoxic conditions at temperatures ranging from 37 degrees to 43 degrees C. Drug alone or heat alone killed a minimum number of cells under aerobic or hypoxic conditions. Exposure to drug and hyperthermia selectively increased the number of ...